Silicone elastomers
Silicone – the all-rounder of elastomers
Alongside the processing of conventional elastomers, R.E.T. has specialised in silicone elastomers. Silicones are silicon-oxygen compounds; different base polymers and fillers provide these elastomers with a variety of properties which enable a wide range of uses
for the products manufactured from them.
Advantages of silicone elastomers are:
- wide usable temperature range from –50°C to +200°C
- very good long-term mechanical durability
- outstanding chemical resistance and age resistance
- broadly adjustable hardness range
- transparent base material, easily dyed
- very good dielectric properties
- approvals for use in the food and medical field
- sterilisable by means of heat or gamma radiation.
HTV silicones vulcanise at high temperature, LSR silicones do so catalytically. These liquid silicone rubbers (LSR) consist of 2 components, which are low-viscosity and thus easily pumped.
The components are mixed in the injection-moulding system.
Additional advantages:
- easy processability and short cycle times bring profitability
- high flowability and good de-moulding behaviour allow moulds and moulded parts with undercuts.
Liquid silicones require a great deal of know-how in mould technology, since the high flowability allows only extremely small gaps at sealing surfaces and parting planes.
VMQ silicone rubber
Material | Synthetic elastomer, peroxide-cured, post-curing necessary. |
|---|---|
Advantages | Very high heat and cold resistance in drying heat. Ageing, ozone and weather-resistant. Moderate oil resistance like CR. Good electrical insulating ability. The physical properties are retained over a large temperature range. Physiologically unobjectionable. |
Disadvantages | moderate mechanical strength. impact-sensitive. Sensitive to exposure to hot water and steam. Combustible. |
FVMQ fluorosilicone rubber
Material | Synthetic elastomer, peroxide-cured, post-curing necessary. |
|---|---|
Advantages | As for silicone rubber but good oil and petrol resistance. |
Disadvantages | Relatively high-priced Combustible. |